C Redding on wed 21 jan 98
Greetings clayarters! I have a quick question that's been bothering me
for quite some time in my classes here at university. Some of the
students dry their clay and their pots with hairdryers. Is this good or
bad? Is there shrinkage involved with the dryer? Is the shrinkage even
or uneven? Should people do it or not do it? Someone asked me about why
these people do it, but I said I wasn't sure...
Clayarters to the rescue?
thanks for your help...
cookie redding
Cindy on thu 22 jan 98
Cookie,
Drying portions of a too-wet pot with a hair dryer can save an otherwise
flop. I prefer my paint stripper or torch, though I seldom use them.
Usually, it's easier and quicker to simply make a new pot. Another use for
a heat source is to firm up a base pot before adding another section to it
to make it taller.
Other than that, just plain impatience, I suppose. But it'd have to be a
very patient impatience to stand there and hold a hairdryer on a pot until
it dried. Placing pots on the lid of a firing kiln is much easier, IMO, and
usually works fine so long as the pot is already a fairly advanced leather
hard. I don't do this with pieces that have large flat bases, however, as
the bases sometimes crack under these conditions.
Cindy in Custer, SD
John Hesselberth on thu 22 jan 98
Any rapid drying process is risky because it results in non uniform
drying and, therefore more of a tendency to crack and/or warp. You might
get away with it if you are just trying to take the excess moisture out
of a piece that has become too soft to work with, but, in general, count
on much higher breaking/cracking/warping losses if you do it. Students
probably do it because they are behind on their assignments and are
trying to get one more piece in the next kiln firing. As you can note
from many of the comments on this forum, most professional potters learn
to slow down the drying process particularly for difficult pieces like
platters.
>----------------------------Original message----------------------------
>
>Greetings clayarters! I have a quick question that's been bothering me
>for quite some time in my classes here at university. Some of the
>students dry their clay and their pots with hairdryers. Is this good or
>bad? Is there shrinkage involved with the dryer? Is the shrinkage even
>or uneven? Should people do it or not do it? Someone asked me about why
>these people do it, but I said I wasn't sure...
>
>Clayarters to the rescue?
>
>thanks for your help...
>
>cookie redding
John Hesselberth
Frog Pond Pottery
Pocopson, PA USA
EMail: john@frogpondpottery.com
visit my web site at http://www.frogpondpottery.com
Cyvonneh on thu 22 jan 98
I've tryed this. I think it works great....except I use a HEAT GUN instead of
a hairdryer..(the heat gun doesn't overheat as quickly as a hair dryer.I've
also only used it for wheel work where I can slowly turn the pot while
simultaneoulsy(sp) holding the gun a few inches from the pot This can be done
before you take the pot from the wheel which deletes the needs for extra bats
and you don't have to wait to trim the pot.( think it wouuld work with hand-
building if you turned the piece on a turntable, lazy susan etc--I have not
needed to dry handbuilt pieces quickly.
Hope this helps!!!
Marcia Selsor on thu 22 jan 98
If you have a problem with hairdryers, you should see Tashiko Takeazo
burn her Sunday NY Times in her large pots. She does this to stiffen the
section before adding a fat coil and throwing some more.
Marcia in Montana
C Redding wrote:
>
> ----------------------------Original message----------------------------
>
> Greetings clayarters! I have a quick question that's been bothering me
> for quite some time in my classes here at university. Some of the
> students dry their clay and their pots with hairdryers. Is this good or
> bad? Is there shrinkage involved with the dryer? Is the shrinkage even
> or uneven? Should people do it or not do it? Someone asked me about why
> these people do it, but I said I wasn't sure...
>
> Clayarters to the rescue?
>
> thanks for your help...
>
> cookie redding
Robert Compton on thu 22 jan 98
> Cookie,
The following is a reprint of an e-mail earlier this year on the
topic of using heat to dry pots, the nutshell answer is it works, but
you need to know the limits..
Robert Compton wrote:
>
> > ----------------------------Original
> > I would like to quickly stiffen up areas of pots in progress on the wheel, e
>
> > Any suggestions as to what to use? I can think of three possible tools:
> > Small propane torch
> > Industrial heat gun
> > hairdryer
>
> David,
>
> All the above ideas work depending on your patience and size of
> vessel. We offer a workshop here on throwing giant pots and since
> participants cannot wait hours to add sections to their pots we have
> gone for the fast approach.
>
> Hairdryers are really slow and like the hotter faster heat guns
> (used as paint strippers, melting glue etc) they are noisy. The little
> fan (blower) in the heat gun or hair dryer can be very annoying.
>
> A propane soldering torch is nice, expecially if you get a
> spreader head, rather than the pencil point tip they come with, but they
> only heat a small area, Ok for small forms that need site hardening.
>
> While giving a workshop on Throwing Oversized Pots, in New
> Zealand, the potters club did not have any of the heating methods just
> mentioned, so they presented me with a small raku burner . When I first
> saw it I was not so sure this was such a good idea. Seemed like killing
> a fly with a sledgehammer, but to the surprise of us all, it turned out
> to be one of the best heaters I had used up till then for large pots (
> 2 -4 ft height).
>
> When I returned to Vermont I modifired this approach by
> using a glassblowers torch. It is smaller than a raku burner, puts out a
> quite, controlled flame, has a plastic (cool to touch handle) and nice
> needle valve for beautiful control. We have several of these in use
> here, along with the hardware store variety soldering torches, raku
> burner and heat guns, but no question these glassblower torches have
> been the best for our uses.
>
> If your interested in getting one Harry Dedell 802-365-4575
> sells them, I am using the hand held torch #2-81 neddle valve torch with
> a RHT torch head ( it is an oversized head) cost about $130. Worth every
> penny if you do any quanity of large pots.
>
> One last tip on using big flames to harden pots for receiving
> the next coil on a throw and coil process. I believe heating the soaking
> wet pots with this intense heat promotes even drying of the coil and
> I've had less problems then when using air (as in a hair dryer). The pot
> is steaming when we finish with the torch ( way too hot to touch the
> pot) by the time a coil is prepared the pot is cool enough to add to and
> the throwing process can proceed almost non stop. I can start and finish
> a large storage jar 2ft diam by 4.5 ft ht in half a day using this
> method, and I tend to work with very soft clay ( makes easy going on
> the wrist and back). One last benifit, to all those potters who love
> fire, the flaming of the pots is great fun.
Robert Compton Pottery http://RobertComptonPottery.com
3600 Rt 116
Bristol, Vermont 05443 802-453-3778
> ----------------------------Original message----------------------------
>
> Greetings clayarters! I have a quick question that's been bothering me
> for quite some time in my classes here at university. Some of the
> students dry their clay and their pots with hairdryers. Is this good or
> bad? Is there shrinkage involved with the dryer? Is the shrinkage even
> or uneven? Should people do it or not do it? Someone asked me about why
> these people do it, but I said I wasn't sure...
>
> Clayarters to the rescue?
>
> thanks for your help...
>
> cookie redding
--
Robert Compton Pottery http://RobertComptonPottery.com
3600 Rt 116
Bristol, Vermont 05443 802-453-3778
DONPREY on fri 23 jan 98
If you can't take the pot out into the sunlight for awhile, a hair dryer is a
handy way to speed the drying of the pot. The whole trick to drying is to do
it EVENLY. It gets harder and harder to do that as you increase the drying
rate. With the hair dryer you have to pay careful attention not to dry one
area significantly ahead of the rest of the pot. If you are really serious
about this, you get a heat gun. What's good is what works.
Don Prey in Oregon
Sandra Dwiggins on fri 23 jan 98
I use a heat gun which is alot more powerful. You just have to make
sure that the pot or the gun keep moving and dry the pot evenly.
Sandy
OWL POTTER on fri 23 jan 98
I have used two hair dryers to stiffen up my pots while throwing for years
with no disastrous results. I position one dryer to blow inside the pot while
the other blows on the outside (this gives me the most even stiffening of the
pot) -while the wheel spins at a very slow speed.
I do it so that I can make the pot wall thinner than normal, or to defy
gravity, or to make the pot stiff enough to remove from the wheel without
distorting its shape. I never have completely dried a pot using this method.
Some shrinkage must be involved, because I am removing water from the clay.
Carolynn Palmer, Somerset Center, Michigan
Paula Sibrack on fri 23 jan 98
Cookie, my students wouldn't be able to finish any work in a short class time
if it weren't for our army of hair dryers. The trick is to use them evenly.
If throwing, keep the hair dryer in one spot and let the wheel move slowly to
distribute the heat. Some ingenius people have even set up artifical arms to
hold the dryer while they go do something else. I sometimes use a heat gun in
my studio, especially when throwing on the mound during humid summer days.
Paula Sibrack, from the woods of Sherman, CT
Unruly JuliE on fri 23 jan 98
I have used a heat gun to dry handbuilt items it works fine. Just
remember to keep the heat moving and do not stay in one place to
long. I used the heat gun to dry clay masks over a plastic form,
the clay had to be just the right dryness to be able to lift off
the form.
JuliE in Michigan where the wind and snow are picking up again
Jack Ward on fri 23 jan 98
To all
I use a propane torch. It`s not what you use,but how you use it!
Jack
in SC
> ----------------------------Original
> message----------------------------
> If you have a problem with hairdryers, you should see Tashiko Takeazo
> burn her Sunday NY Times in her large pots. She does this to stiffen
> the
> section before adding a fat coil and throwing some more.
> Marcia in Montana
>
> C Redding wrote:
> >
> > ----------------------------Original
> message----------------------------
> >
> > Greetings clayarters! I have a quick question that's been bothering
> me
> > for quite some time in my classes here at university. Some of the
> > students dry their clay and their pots with hairdryers. Is this
> good or
> > bad? Is there shrinkage involved with the dryer? Is the shrinkage
> even
> > or uneven? Should people do it or not do it? Someone asked me
> about why
> > these people do it, but I said I wasn't sure...
> >
> > Clayarters to the rescue?
> >
> > thanks for your help...
> >
> > cookie redding
Dee Clay on sat 24 jan 98
The question seems to be hair dryer or torch.
Being in hot Miami I just can't think of using either. I always have a floor
fan or ocolating fan handy. I use this in my classes because we can get
several pots dried at one time.
And when the A/C isn't working we just set it up facing us and cool us off
while drying clay.
Ofcourse we can't dry small areas but my class is only 2 hours once a week so
getting leather hard fast is sometimes important.
Today is humid and nothing is drying.
Diane
deeclay@aol.com
David on sun 25 jan 98
Once during a workshop with Catherine Hiersoux, she suspended a bare light
bulb inside of a very large porcelain piece she had just thrown, set the
wheel to rotate slowly and went on to other things. It worked well, not as
well as a heat torch I imagine however.
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